If Lamb is currently one of the Royal Ballet's busiest principals, it's partly because she's so unusually versatile. To the classics, she brings a crystalline technique and an almost old-fashioned, theatrical glamour; in the more contemporary repertory, she's audacious, clever and fast. It doesn't hurt that even in her scruffy rehearsal clothes, sitting in a pokey office at the Opera House, she still manages to look like a picture-book ballerina, with her perfectly symmetrical oval face, blond hair and milky skin.

It is a romp. Illogical, rampageously silly, laid – like some abandoned tot – at Lord Byron’s door, Le Corsaire boasts a 19th-century history that saw it taken within two years from Paris in 1856 to St Petersburg.